Procrastination and fits of disappointment aside we're a day or so from building a few walls and hanging drywall.I had decided against drywall that absorbs sound ($95.00 per sheet) but thought I would get an opinion or two first.Is there anything to be gained over a second layer of standard drywall that justifies the cost?

From what I have seen on other forums, double drywall with green glue is the most oft used system. If there is space behind the drywall, say with studs roxull can be used for sound absorption. The green glue apparently dissipates the sound wave energy as heat.

Procrastination and fits of disappointment aside we're a day or so from building a few walls and hanging drywall.I had decided against drywall that absorbs sound ($95.00 per sheet) but thought I would get an opinion or two first.Is there anything to be gained over a second layer of standard drywall that justifies the cost?

Now, not that I know anything ;), but what are you wanting to accomplish?

More drywall won't actually absorb sound. As for sound absorbing drywall, really it is a "drywall sandwich" of sorts. Two dense layers (many are two traditional drywall layers others have 1 traditional drywall layer and a second dense layer) and a visco-elastic layer in the middle. And it doesn't usually help with the acoustic in the room, but it does help with keeping sounds in (or out) of the room. Two different subjects (soundproofing vs. acoustics).

That is the "pre-made" version of the super popular DD+GG (Double Drywall + Green Glue) that many people do. In fact, the DD+GG should yield the same if not better sound dampening for a LOT less money, but makes a little more mess and is a little more DIY obviously.

Green Glue is starting to be offered at more home improvement stores making it easy to get. The cheapest is still to order by the big 5 gallon buckets, but you will also need one of the "speedloader" type of caulk guns. It is easier to go with the tubes, but it takes a lot more than you think.

Again, let me know what you are wanting to accomplish, and I can draft a game plan.

The room which lent itself to the becoming this dedicated space is directly below 2 bedrooms and shares a common weight bearing wall with the master bedroom above and beside it. I can't make it sound proof so here's what I'm thinking...The room becomes wider (12'6" instead of 10'6")below this part of the house.My kids are used to my noise but the wife sleeps lightly and would rather not have to listen me at night.At the moment we're insulating the roof with double 4" (edit: looks like its 3", considering going 3 pieces thick) batons of Roxul safe and sound which will get new t-bar and new ceiling tile recommended for the space.The common wall is going to be stripped of its drywall, have Roxul added at which time a second wall and second layer of Roxul will be added.Double drywall will be added around the room.

The room which lent itself to the becoming this dedicated space is directly below 2 bedrooms and shares a common weight bearing wall with the master bedroom above and beside it. I can't make it sound proof so here's what I'm thinking...The room becomes wider (12'6" instead of 10'6")below this part of the house.My kids are used to my noise but the wife sleeps lightly and would rather not have to listen me at night.At the moment we're insulating the roof with double 4" (edit: looks like its 3", considering going 3 pieces thick) batons of Roxul safe and sound which will get new t-bar and new ceiling tile recommended for the space.The common wall is going to be stripped of its drywall, have Roxul added at which time a second wall and second layer of Roxul will be added.Double drywall will be added around the room.

Yeah, I'm already on the hunt for some.Seems this is going to be a perfect storm of a room.I played the radio in the kids room and went down and it was fairly clear, might as well have been in the same room.Looks like they loaded the wrong insulation (contractor brought back the wrong insulation). Might look at redoing some outside walls while we're at it. I have a full day to decide before he comes back to the house.So if I can't get green glue what's the next best option? Can a different kind of caulk or silicone be used?I've even considered installing drywall (possibly the expensive drywall) above the T-bar ceiling, seam sealed with some caulking.Its already not looking to good.Good thing I have another room, this might take a while.Procrastination bad...

Good (high R value) "pink fluffy" insulation will work WONDERS for what you are trying to do. No need to go Roxul if you don't want. The type of insulation is NOT your weak links.

Any air ducts are link perfect communication conduits for sound from one room to the next. If you can even replace some of it with 8 to 10 feet of flexible insulated duct (not too pricey) and put a few bends into it, the sound will get absorbed a lot and not pass from the theater room to the rest of the house. I thing that I used two 15 foot pieces (one for each duct) and I could put one end up to my ear and have someone yell in the other end and not hear it... Seriously.

The other major issue is that you don't have enough "stuff" to stop the sound. For the walls, the double drywall (5/8" if possible) is your "mass." More mass means it takes more energy (sound waves) to move it, thus it dampens the sound. That is also for your ceiling.

Add the Green Glue (heavy on the ceiling if you are doing DD up there) and it adds that visco-elactic element that literly dampens even more vibration and creates a barrier between the two sheets of drywall to reduce sound transmission from one sheet to the one behind it.

Which gets me to decoupling. This is where some people will go staggered stud wall like I did, or a double wall "room within a room". This really holds the sound in (and out) by not giving it a solid path to go from inside the room, through the drywall, through the stud, through the outside drywall, and into the air outside the room. For me, I planned on just loading up a lot with Green Glue on the ceiling as our master bedroom is right above the theater, but I quickly learned that I would not be happy with that. So I ended up with Whisper Clips from SoundProofingCompany.com (where I also got my Green Glue at an "AVS Member" discount price), and bought the hat channel locally for less than I thought, and I decoupled my ceiling as well. I was really amazed at how much sound is now trapped in the theater. Sure, some LFE stuff gets out, but lets be real. It takes something just short of a nuclear bunker to hold super low frequencies back. I can, however, easily watch a sci-fi flick with all sorts of explosions and special effects craziness at a pretty good volume (louder than my wife likes in in the theater) and she can be in the bedroom and not wake up. To me, that is a success. I can't image what it would be like if I hadn't spent the extra $100 or so to decouple the most important "wall" in my theater... the ceiling...

I know you are at the 11th hour on getting moving on this, but just think about it before jumping one way or another and for a little extra time and a little extra effort (clips and channels are actually pretty easy to work with) you can know that you took it to "the next level" without going stupid crazy/expensive.

If not, hey it is your call. I can only offer advice. You must choose what fits for your needs/wants/dollars.

Thanks, I'll look into this some more.Regarding the 11th hour, I have until May for this dedicated room. It was a deadline I set for myself a while back.The procrastination related to the new towers, I knew they were coming and I did want to unpack them in their new room (might have to go as far as to name them...).I'm exited.The contractor I hired is looking to subsidize his full time semi retired/semi seasonal employment by helping me out.I figured since I'm better at making money than installing insulation and finishing drywall I'd let him start asap which turned out to be today.Assuming I can get green glue in Canada I will go this route.I read somewhere to use different thickness's of drywall (1/2 and 5/8) together when using green glue. I have no positive memories from drywalling in the past, I figured I'd just go with it.The ceiling is going to be the enemy here. I'll keep looking for the clips and channels. My main concern is the weight. I can only imagine how it would feel to have a 5/8' sheet of drywall fall on a friend or family member. I don't trust the idea that less screws can hold more weight. The pattern shown online concerns me (every 24"? if I remember correctly).The insulation he brought back is R22 Roxul 8 bundles for $375.00.Not sure what the pink stuff cost. Any chance its cheaper and better?